sylvainsjc, thanks for the supposition, but is isn't my case: I have not pulseaudio installed.

Based on your observation of nothing really happening, I suspect something is waiting for something else to complete.
This conclusion has been reached before unfortunately, and it is difficult to determine what is causing the startup process to hang in this manner.

Can you check to see if any "kcminit" or "kbuildsycoca4" processes are running during this time? (Although it would be odd for them to not be using CPU/Disk)

Sorry I can't to look at kcminit or kbuildsycoca4. The thing is, I have surrendered and renamed ~/.kde4 - and already reconfigured almost all DE parts. Before reconfiguring I have tried new clean account and haven't got the issue.

Yes, I have had ~/.kde4 with very long history

Okay, that indicates an application configuration is definitely the cause. Good to see you have found a solution in any case (I suspect it was a network timeout of some description).